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Leung ECH, Jain P, Michealson MA, Choi H, Ellsworth-Kopkowski A, Valenzuela CF. Recent breakthroughs in understanding the cerebellum's role in fetal alcohol spectrum disorder: A systematic review. Alcohol 2023; 119:37-71. [PMID: 38097146 PMCID: PMC11166889 DOI: 10.1016/j.alcohol.2023.12.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Revised: 12/07/2023] [Accepted: 12/08/2023] [Indexed: 06/14/2024]
Abstract
Exposure to alcohol during fetal development can lead to structural and functional abnormalities in the cerebellum, a brain region responsible for motor coordination, balance, and specific cognitive functions. In this systematic review, we comprehensively analyze a vast body of research conducted on vertebrate animals and humans over the past 13 years. We identified studies through PubMed and screened them following PRISMA guidelines. Data extraction and quality analysis were conducted using Covidence systematic review software. A total of 108 studies met our inclusion criteria, with the majority (79 studies) involving vertebrate animal models and 29 studies focusing on human subjects. Animal models included zebrafish, mice, rats, sheep, and non-human primates, investigating the impact of ethanol on cerebellar structure, gene/protein expression, physiology, and cerebellar-dependent behaviors. Additionally, some animal studies explored potential therapeutic interventions against ethanol-induced cerebellar damage. The human studies predominantly adopted cohort designs, exploring the effects of prenatal alcohol exposure on cerebellar structure and function. Certain human studies delved into innovative cerebellar-based diagnostic approaches for fetal alcohol spectrum disorder (FASD). The collective findings from these studies clearly indicate that the cerebellum is involved in various neurophysiological deficits associated with FASD, emphasizing the importance of evaluating both cerebellar structure and function in the diagnostic process for this condition. Moreover, this review sheds light into potential therapeutic strategies that can mitigate prenatal alcohol exposure-induced cerebellar damage.
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Affiliation(s)
- Eric C H Leung
- Department of Neurosciences, School of Medicine, University of New Mexico Health Sciences Center, Albuquerque, NM 87131, United States
| | - Priyanka Jain
- Department of Neurosciences, School of Medicine, University of New Mexico Health Sciences Center, Albuquerque, NM 87131, United States
| | - Marisa A Michealson
- Department of Neurosciences, School of Medicine, University of New Mexico Health Sciences Center, Albuquerque, NM 87131, United States
| | - Hyesun Choi
- Department of Neurosciences, School of Medicine, University of New Mexico Health Sciences Center, Albuquerque, NM 87131, United States
| | - Alexis Ellsworth-Kopkowski
- Health Sciences Library & Informatics Center, University of New Mexico Health Sciences Center, Albuquerque, NM 87131, United States
| | - C Fernando Valenzuela
- Department of Neurosciences, School of Medicine, University of New Mexico Health Sciences Center, Albuquerque, NM 87131, United States.
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2
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Luhmann HJ. Malformations-related neocortical circuits in focal seizures. Neurobiol Dis 2023; 178:106018. [PMID: 36706927 DOI: 10.1016/j.nbd.2023.106018] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Revised: 01/18/2023] [Accepted: 01/23/2023] [Indexed: 01/25/2023] Open
Abstract
This review article gives an overview on the molecular, cellular and network mechanisms underlying focal seizures in neocortical networks with developmental malformations. Neocortical malformations comprise a large variety of structural abnormalities associated with epilepsy and other neurological and psychiatric disorders. Genetic or acquired disorders of neocortical cell proliferation, neuronal migration and/or programmed cell death may cause pathologies ranging from the expression of dysmorphic neurons and heterotopic cell clusters to abnormal layering and cortical misfolding. After providing a brief overview on the pathogenesis and structure of neocortical malformations in humans, animal models are discussed and how they contributed to our understanding on the mechanisms of neocortical hyperexcitability associated with developmental disorders. State-of-the-art molecular biological and electrophysiological techniques have been also used in humans and on resectioned neocortical tissue of epileptic patients and provide deep insights into the subcellular, cellular and network mechanisms contributing to focal seizures. Finally, a brief outlook is given how novel models and methods can shape translational research in the near future.
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Affiliation(s)
- Heiko J Luhmann
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University Mainz, Duesbergweg 6, Mainz, Germany.
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3
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Wang J, Fan M, Yin S, Xu X, Fu B, Jiang R, Sun L. Ginseng oligosaccharides (GSO) inhibit C48/80-stimulated pseudoallergic mechanisms through the PLC/Ca2+/PKC/MAPK/c-Fos signaling pathway. J Funct Foods 2022. [DOI: 10.1016/j.jff.2022.105211] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2022] Open
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4
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Özkul B, Urfalı FE, Sever İH, Bozkurt MF, Söğüt İ, Elgörmüş ÇS, Erdogan MA, Erbaş O. Demonstration of Ameliorating Effect of Vardenafil Through Its Anti-Inflammatory and Neuroprotective Properties in Autism Spectrum Disorder Induced by Propionic Acid on Rat Model. Int J Neurosci 2022; 132:1150-1164. [PMID: 35584252 DOI: 10.1080/00207454.2022.2079507] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Introduction: Autism spectrum disorder (ASD) is a neurodevelopmental disorder with complex etiology. In this study, we aimed to determine the ameliorating effects of vardenafil in the ASD rat model induced by propionic acid (PPA) in terms of neurobehavioral changes and also support these effects with histopathological changes, brain biochemical analysis and magnetic resonance spectroscopy (MRS) findings.Materials and Methods: Twenty-one male rats were randomly assigned into 3 groups. Group 1 (control, 7 rats) did not receive treatment. Rats in groups 2 and 3 were given PPA at the dose of 250 mg/kg/day intraperitoneally for 5 days. After PPA administration, animals in group 2 (PPAS, 7 rats) were given saline and animals in group 3 (PPAV, 7 rats) were given vardenafil. Behavioral tests were performed between the 20th and 24th days of the study. The rats were taken for MRS on the 25th day. At the end of the study, brain levels of interleukin-2 (IL-2), IL-17, tumor necrosis factor-α, nerve growth factor, cGMP and lactate levels were measured. In the cerebellum and the CA1 and CA3 regions of the hippocampus, counts of neurons and Purkinje cells and glial fibrillary acidic protein (associated with gliosis) were evaluated histologically.Results: Three chamber sociability and passive avoiding test, histopathological results, lactate levels derived from MRS, and biochemical biomarkers revealed significant differences among the PPAV and PPAS groups.Conclusion: We concluded that vardenafil improves memory and social behaviors and prevent loss of neuronal and Purkinje cell through its anti-inflammatory and neuroprotective effect.
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Affiliation(s)
- Bahattin Özkul
- Faculty of Medicine, Department of Radiology, Istanbul Atlas University, Istanbul, Turkey
| | - Furkan Ertürk Urfalı
- Department of Radiology, Faculty of Medicine, Kutahya Saglık Bilimleri, Kutahya, Turkey
| | - İbrahim Halil Sever
- Department of Radiology, Faculty of Medicine, Demiroğlu Bilim University, Istanbul, Turkey
| | - Mehmet Fatih Bozkurt
- Department of Pathology, Faculty of Veterinary, Afyon Kocatepe University, Afyon, Turkey
| | - İbrahim Söğüt
- Department of Biochemistry, Faculty of Medicine, Demiroğlu Bilim University, Istanbul, Turkey
| | - Çağrı Serdar Elgörmüş
- Department of Emergency, Faculty of Medicine, Istanbul Atlas University, Istanbul, Turkey
| | - Mumin Alper Erdogan
- Department of Physiology, Faculty of Medicine, Izmir Katip Celebi University, Izmir, Turkey
| | - Oytun Erbaş
- Department of Physiology, Faculty of Medicine, Demiroğlu Bilim University, Istanbul, Turkey
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5
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Komuro Y, Galas L, Morozov YM, Fahrion JK, Raoult E, Lebon A, Tilot AK, Kikuchi S, Ohno N, Vaudry D, Rakic P, Komuro H. The Role of Galanin in Cerebellar Granule Cell Migration in the Early Postnatal Mouse during Normal Development and after Injury. J Neurosci 2021; 41:8725-8741. [PMID: 34462307 PMCID: PMC8528496 DOI: 10.1523/jneurosci.0900-15.2021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2015] [Revised: 08/16/2021] [Accepted: 08/19/2021] [Indexed: 11/21/2022] Open
Abstract
Galanin, one of the most inducible neuropeptides, is widely present in developing brains, and its expression is altered by pathologic events (e.g., epilepsy, ischemia, and axotomy). The roles of galanin in brain development under both normal and pathologic conditions have been hypothesized, but the question of how galanin is involved in fetal and early postnatal brain development remains largely unanswered. In this study, using granule cell migration in the cerebellum of early postnatal mice (both sexes) as a model system, we examined the role of galanin in neuronal cell migration during normal development and after brain injury. Here we show that, during normal development, endogenous galanin participates in accelerating granule cell migration via altering the Ca2+ and cAMP signaling pathways. Upon brain injury induced by the application of cold insults, galanin levels decrease at the lesion sites, but increase in the surroundings of lesion sites. Granule cells exhibit the following corresponding changes in migration: (1) slowing down migration at the lesion sites; and (2) accelerating migration in the surroundings of lesion sites. Experimental manipulations of galanin signaling reduce the lesion site-specific changes in granule cell migration, indicating that galanin plays a role in such deficits in neuronal cell migration. The present study suggests that manipulating galanin signaling may be a potential therapeutic target for acutely injured brains during development.SIGNIFICANCE STATEMENT Deficits in neuronal cell migration caused by brain injury result in abnormal development of cortical layers, but the underlying mechanisms remain to be determined. Here, we report that on brain injury, endogenous levels of galanin, a neuropeptide, are altered in a lesion site-specific manner, decreasing at the lesion sites but increasing in the surroundings of lesion sites. The changes in galanin levels positively correlate with the migration rate of immature neurons. Manipulations of galanin signaling ameliorate the effects of injury on neuronal migration and cortical layer development. These results shed a light on galanin as a potential therapeutic target for acutely injured brains during development.
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Affiliation(s)
- Yutaro Komuro
- Department of Neurosciences, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio 44195
| | - Ludovic Galas
- Regional Platform for Cell Imaging of Normandy, INSERM, Université de Rouen Normandie, 76000 Rouen, France
| | - Yury M Morozov
- Department of Neuroscience, Yale University School of Medicine, New Haven, Connecticut 06510
| | - Jennifer K Fahrion
- Department of Neurosciences, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio 44195
| | - Emilie Raoult
- Regional Platform for Cell Imaging of Normandy, INSERM, Université de Rouen Normandie, 76000 Rouen, France
| | - Alexis Lebon
- Regional Platform for Cell Imaging of Normandy, INSERM, Université de Rouen Normandie, 76000 Rouen, France
| | - Amanda K Tilot
- Department of Genomic Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio 44195
| | - Shin Kikuchi
- Department of Neurosciences, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio 44195
| | - Nobuhiko Ohno
- Department of Neurosciences, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio 44195
- Division of Neurobiology and Bioinformatics, National Institute for Physiological Sciences, Aichi 444-8787, Japan
- Department of Anatomy, Division of Histology and Cell Biology, School of Medicine, Jichi Medical University, Tochigi 329-0498, Japan
| | - David Vaudry
- Regional Platform for Cell Imaging of Normandy, INSERM, Université de Rouen Normandie, 76000 Rouen, France
- Neuropeptides, Neuronal Death and Cell Plasticity Team, Laboratory of Neuronal and Neuroendocrine Communication and Differentiation, INSERM U1239, Université de Rouen Normandie, 76000 Rouen, France
| | - Pasko Rakic
- Department of Neuroscience, Yale University School of Medicine, New Haven, Connecticut 06510
- Kavli Institute for Neuroscience, Yale School of Medicine, New Haven, Connecticut 06510
| | - Hitoshi Komuro
- Department of Neurosciences, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio 44195
- Department of Neuroscience, Yale University School of Medicine, New Haven, Connecticut 06510
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6
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Non-Smad, BMP-dependent signaling protects against the effects of acute ethanol toxicity. Toxicol Lett 2021; 353:118-126. [PMID: 34687774 DOI: 10.1016/j.toxlet.2021.10.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Revised: 10/09/2021] [Accepted: 10/18/2021] [Indexed: 01/20/2023]
Abstract
This study explores the effect of acute Ethanol (EtOH) exposure on Bone Morphogenetic Protein (BMP)-evoked intracellular signaling, and the concomitant morphological changes induced by EtOH in C2C12 cells and DRG (Dorsal root ganglion) neurons in an in vitro model related to Fetal Alcohol Syndrome Disorder (FASD). All assays were performed within 30 min of BMP stimulation to specifically investigate the earliest events occurring in BMP-evoked intracellular signaling pathways. We show that Smad phosphorylation and nuclear translocation stimulated by BMPs was not altered following acute exposure to EtOH. In contrast, acute EtOH exposure alone caused a striking concentration-dependent decrease in Akt phosphorylation, as well as a loss of adhesion in C2C12 cells. The addition of BMPs before exposure to EtOH was associated with maintenance of Akt phosphorylation, greater cell adhesion in C2C12 cells, and preservation of growth cone complexity in DRG neurons. Thus, for both C2C12 cells and DRG neurons, BMPs, acting through non-canonical BMP signaling pathways, appear to impart some protection against the profound effects of acute EtOH exposure on cellular adhesion and structure.
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7
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Delhaye S, Bardoni B. Role of phosphodiesterases in the pathophysiology of neurodevelopmental disorders. Mol Psychiatry 2021; 26:4570-4582. [PMID: 33414502 PMCID: PMC8589663 DOI: 10.1038/s41380-020-00997-9] [Citation(s) in RCA: 44] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/04/2020] [Revised: 12/03/2020] [Accepted: 12/09/2020] [Indexed: 12/12/2022]
Abstract
Phosphodiesterases (PDEs) are enzymes involved in the homeostasis of both cAMP and cGMP. They are members of a family of proteins that includes 11 subfamilies with different substrate specificities. Their main function is to catalyze the hydrolysis of cAMP, cGMP, or both. cAMP and cGMP are two key second messengers that modulate a wide array of intracellular processes and neurobehavioral functions, including memory and cognition. Even if these enzymes are present in all tissues, we focused on those PDEs that are expressed in the brain. We took into consideration genetic variants in patients affected by neurodevelopmental disorders, phenotypes of animal models, and pharmacological effects of PDE inhibitors, a class of drugs in rapid evolution and increasing application to brain disorders. Collectively, these data indicate the potential of PDE modulators to treat neurodevelopmental diseases characterized by learning and memory impairment, alteration of behaviors associated with depression, and deficits in social interaction. Indeed, clinical trials are in progress to treat patients with Alzheimer's disease, schizophrenia, depression, and autism spectrum disorders. Among the most recent results, the application of some PDE inhibitors (PDE2A, PDE3, PDE4/4D, and PDE10A) to treat neurodevelopmental diseases, including autism spectrum disorders and intellectual disability, is a significant advance, since no specific therapies are available for these disorders that have a large prevalence. In addition, to highlight the role of several PDEs in normal and pathological neurodevelopment, we focused here on the deregulation of cAMP and/or cGMP in Down Syndrome, Fragile X Syndrome, Rett Syndrome, and intellectual disability associated with the CC2D1A gene.
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Affiliation(s)
- Sébastien Delhaye
- grid.429194.30000 0004 0638 0649Université Côte d’Azur, CNRS UMR7275, Institute of Molecular and Cellular Pharmacology, 06560 Valbonne, France
| | - Barbara Bardoni
- Université Côte d'Azur, Inserm, CNRS UMR7275, Institute of Molecular and Cellular Pharmacology, 06560, Valbonne, France.
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8
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Martín-Estal I, Castilla-Cortázar I, Castorena-Torres F. The Placenta as a Target for Alcohol During Pregnancy: The Close Relation with IGFs Signaling Pathway. Rev Physiol Biochem Pharmacol 2021; 180:119-153. [PMID: 34159446 DOI: 10.1007/112_2021_58] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Alcohol is one of the most consumed drugs in the world, even during pregnancy. Its use is a risk factor for developing adverse outcomes, e.g. fetal death, miscarriage, fetal growth restriction, and premature birth, also resulting in fetal alcohol spectrum disorders. Ethanol metabolism induces an oxidative environment that promotes the oxidation of lipids and proteins, triggers DNA damage, and advocates mitochondrial dysfunction, all of them leading to apoptosis and cellular injury. Several organs are altered due to this harmful behavior, the brain being one of the most affected. Throughout pregnancy, the human placenta is one of the most important organs for women's health and fetal development, as it secretes numerous hormones necessary for a suitable intrauterine environment. However, our understanding of the human placenta is very limited and even more restricted is the knowledge of the impact of toxic substances in its development and fetal growth. So, could ethanol consumption during this period have wounding effects in the placenta, compromising proper fetal organ development? Several studies have demonstrated that alcohol impairs various signaling cascades within G protein-coupled receptors and tyrosine kinase receptors, mainly through its action on insulin and insulin-like growth factor 1 (IGF-1) signaling pathway. This last cascade is involved in cell proliferation, migration, and differentiation and in placentation. This review tries to examine the current knowledge and gaps in our existing understanding of the ethanol effects in insulin/IGFs signaling pathway, which can explain the mechanism to elucidate the adverse actions of ethanol in the maternal-fetal interface of mammals.
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Affiliation(s)
- Irene Martín-Estal
- Tecnologico de Monterrey, Escuela de Medicina y Ciencias de la Salud, Monterrey, NL, Mexico
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9
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Morishita S, Hokamura K, Yoshikawa A, Agata N, Tsutsui Y, Umemura K, Kumada T. Different exercises can modulate the differentiation/maturation of neural stem/progenitor cells after photochemically induced focal cerebral infarction. Brain Behav 2020; 10:e01535. [PMID: 31989796 PMCID: PMC7066356 DOI: 10.1002/brb3.1535] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Revised: 12/05/2019] [Accepted: 12/23/2019] [Indexed: 12/21/2022] Open
Abstract
INTRODUCTION Exercise therapies during rehabilitation significantly promote recovery from various deficits after cerebral infarction, which is mediated by neuronal plasticity with distinct inputs. Although adult neurogenesis can also be modulated by neuronal activity before synaptogenesis, how distinct exercises contribute to the neurological reorganization of the injured cerebral cortex remains unclear. In the present study, we aimed to elucidate the effects of different exercise therapies on motor recovery and neuronal reorganization after photochemically induced focal cerebral infarction. METHODS Here, we examined the effects of three different exercises-(a) forced lower-intensity and (b) higher-intensity treadmill exercises, and (c) voluntary exercise with wheel running-on motor recovery and adult neurogenesis in a rat model of focal cerebral infarction. Photochemically induced thrombosis (PIT) was used to generate focal infarction in rats that was mostly confined to their motor cortices. RESULTS Beam walking tests showed that recovery after PIT-induced cortical infarction differed in acute and chronic stages and was influenced by the type of exercise. Furthermore, forced low-intensity training had more positive effects on functional recovery than other exercises or control. To evaluate the production of newly generated cells including de novo neurogenesis, we performed lineage analysis with BrdU labeling and immunofluorescence experiments. Lower-intensity treadmill exercise increased the number of BrdU/NeuN colabeled cells, but not total BrdU-retaining or BrdU/Sox2-colabeled cells, in the peri-infarct region of the ipsilateral cortex. In contrast, high-intensity treadmill or voluntary exercises had the opposite effects. CONCLUSIONS These results suggest that neuronal maturation can be differently modulated by distinct exercises and that low-intensity treadmill exercise could result in more potent generation of mature neurons. This also suggests the possibility that the generation of neural stem/progenitor cells and differentiation might be modulated by rehabilitation-mediated neural plasticity.
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Affiliation(s)
- Saho Morishita
- Department of Health and Nutritional SciencesFaculty of Health Promotional SciencesTokoha UniversityHamamatsuJapan
- Department of PharmacologyHamamatsu University School of MedicineHamamatsuJapan
| | - Kazuya Hokamura
- Department of PharmacologyHamamatsu University School of MedicineHamamatsuJapan
| | - Akira Yoshikawa
- Department of PhysiologyShowa University School of MedicineTokyoJapan
| | - Nobuhide Agata
- Faculty of Health and Medical SciencesTokoha UniversityHamamatsuJapan
| | - Yoshihiro Tsutsui
- Faculty of Health and Medical SciencesTokoha UniversityHamamatsuJapan
| | - Kazuo Umemura
- Department of PharmacologyHamamatsu University School of MedicineHamamatsuJapan
| | - Tatsuro Kumada
- Faculty of Health and Medical SciencesTokoha UniversityHamamatsuJapan
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10
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Skorput AG, Lee SM, Yeh PW, Yeh HH. The NKCC1 antagonist bumetanide mitigates interneuronopathy associated with ethanol exposure in utero. eLife 2019; 8:48648. [PMID: 31545168 PMCID: PMC6768659 DOI: 10.7554/elife.48648] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Accepted: 09/22/2019] [Indexed: 11/15/2022] Open
Abstract
Prenatal exposure to ethanol induces aberrant tangential migration of corticopetal GABAergic interneurons, and long-term alterations in the form and function of the prefrontal cortex. We have hypothesized that interneuronopathy contributes significantly to the pathoetiology of fetal alcohol spectrum disorders (FASD). Activity-dependent tangential migration of GABAergic cortical neurons is driven by depolarizing responses to ambient GABA present in the cortical enclave. We found that ethanol exposure potentiates the depolarizing action of GABA in GABAergic cortical interneurons of the embryonic mouse brain. Pharmacological antagonism of the cotransporter NKCC1 mitigated ethanol-induced potentiation of GABA depolarization and prevented aberrant patterns of tangential migration induced by ethanol in vitro. In a model of FASD, maternal bumetanide treatment prevented interneuronopathy in the prefrontal cortex of ethanol exposed offspring, including deficits in behavioral flexibility. These findings position interneuronopathy as a mechanism of FASD symptomatology, and posit NKCC1 as a pharmacological target for the management of FASD.
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Affiliation(s)
- Alexander Gj Skorput
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Hanover, United States.,Department of Neuroscience, School of Medicine, University of Minnesota Twin Cities, Minneapolis, United States
| | - Stephanie M Lee
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Hanover, United States
| | - Pamela Wl Yeh
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Hanover, United States
| | - Hermes H Yeh
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Hanover, United States
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11
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Hwang HM, Ku RY, Hashimoto-Torii K. Prenatal Environment That Affects Neuronal Migration. Front Cell Dev Biol 2019; 7:138. [PMID: 31380373 PMCID: PMC6652208 DOI: 10.3389/fcell.2019.00138] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Accepted: 07/08/2019] [Indexed: 11/22/2022] Open
Abstract
Migration of neurons starts in the prenatal period and continues into infancy. This developmental process is crucial for forming a proper neuronal network, and the disturbance of this process results in dysfunction of the brain such as epilepsy. Prenatal exposure to environmental stress, including alcohol, drugs, and inflammation, disrupts neuronal migration and causes neuronal migration disorders (NMDs). In this review, we summarize recent findings on this topic and specifically focusing on two different modes of migration, radial, and tangential migration during cortical development. The shared mechanisms underlying the NMDs are discussed by comparing the molecular changes in impaired neuronal migration under exposure to different types of prenatal environmental stress.
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Affiliation(s)
- Hye M Hwang
- Center for Neuroscience Research, Children's National Medical Center, The Children's Research Institute, Washington, DC, United States.,The Institute for Biomedical Sciences, School of Medicine and Health Sciences, The George Washington University, Washington, DC, United States
| | - Ray Y Ku
- Center for Neuroscience Research, Children's National Medical Center, The Children's Research Institute, Washington, DC, United States
| | - Kazue Hashimoto-Torii
- Center for Neuroscience Research, Children's National Medical Center, The Children's Research Institute, Washington, DC, United States.,Departments of Pediatrics, and Pharmacology & Physiology, School of Medicine and Health Sciences, The George Washington University, Washington, DC, United States
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12
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Wang L, Zhang L, Chow BKC. Secretin Modulates the Postnatal Development of Mouse Cerebellar Cortex Via PKA- and ERK-dependent Pathways. Front Cell Neurosci 2017; 11:382. [PMID: 29249942 PMCID: PMC5714926 DOI: 10.3389/fncel.2017.00382] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2017] [Accepted: 11/17/2017] [Indexed: 12/14/2022] Open
Abstract
Postnatal development of the cerebellum is critical for its intact function such as motor coordination and has been implicated in the pathogenesis of psychiatric disorders. We previously reported that deprivation of secretin (SCT) from cerebellar Purkinje neurons impaired motor coordination and motor learning function, while leaving the potential role of SCT in cerebellar development to be determined. SCT and its receptor (SCTR) were constitutively expressed in the postnatal cerebellum in a temporal and cell-specific manner. Using a SCT knockout mouse model, we provided direct evidence showing altered developmental patterns of Purkinje cells (PCs) and granular cells (GCs). SCT deprivation reduced the PC density, impaired the PC dendritic formation, induced accelerated GC migration and potentiated cerebellar apoptosis. Furthermore, our results indicated the involvement of protein kinase A (PKA) and extracellular signal regulated kinase (ERK) signaling pathways in SCT-mediated protective effects against neuronal apoptosis. Results of this study illustrated a novel function of SCT in the postnatal development of cerebellum, emphasizing the necessary role of SCT in cerebellar-related functions.
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Affiliation(s)
- Lei Wang
- School of Biological Sciences, University of Hong Kong, Pokfulam, Hong Kong
| | - Li Zhang
- GHM Institute of CNS Regeneration, Jinan University, Guangzhou, China
| | - Billy K. C. Chow
- School of Biological Sciences, University of Hong Kong, Pokfulam, Hong Kong
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13
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Kirischuk S, Sinning A, Blanquie O, Yang JW, Luhmann HJ, Kilb W. Modulation of Neocortical Development by Early Neuronal Activity: Physiology and Pathophysiology. Front Cell Neurosci 2017; 11:379. [PMID: 29238291 PMCID: PMC5712676 DOI: 10.3389/fncel.2017.00379] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Accepted: 11/13/2017] [Indexed: 12/23/2022] Open
Abstract
Animal and human studies revealed that patterned neuronal activity is an inherent feature of developing nervous systems. This review summarizes our current knowledge about the mechanisms generating early electrical activity patterns and their impact on structural and functional development of the cerebral cortex. All neocortical areas display distinct spontaneous and sensory-driven neuronal activity patterns already at early phases of development. At embryonic stages, intermittent spontaneous activity is synchronized within small neuronal networks, becoming more complex with further development. This transition is accompanied by a gradual shift from electrical to chemical synaptic transmission, with a particular role of non-synaptic tonic currents before the onset of phasic synaptic activity. In this review article we first describe functional impacts of classical neurotransmitters (GABA, glutamate) and modulatory systems (e.g., acetylcholine, ACh) on early neuronal activities in the neocortex with special emphasis on electrical synapses, nonsynaptic and synaptic currents. Early neuronal activity influences probably all developmental processes and is crucial for the proper formation of neuronal circuits. In the second part of our review, we illustrate how specific activity patterns might interfere with distinct neurodevelopmental processes like proliferation, migration, axonal and dendritic sprouting, synapse formation and neurotransmitter specification. Finally, we present evidence that transient alterations in neuronal activity during restricted perinatal periods can lead to persistent changes in functional connectivity and therefore might underlie the manifestation of neurological and neuropsychiatric diseases.
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Affiliation(s)
- Sergei Kirischuk
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Anne Sinning
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Oriane Blanquie
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Jenq-Wei Yang
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Heiko J Luhmann
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Werner Kilb
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
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14
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Galas L, Bénard M, Lebon A, Komuro Y, Schapman D, Vaudry H, Vaudry D, Komuro H. Postnatal Migration of Cerebellar Interneurons. Brain Sci 2017; 7:brainsci7060062. [PMID: 28587295 PMCID: PMC5483635 DOI: 10.3390/brainsci7060062] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2017] [Revised: 05/25/2017] [Accepted: 06/01/2017] [Indexed: 12/26/2022] Open
Abstract
Due to its continuing development after birth, the cerebellum represents a unique model for studying the postnatal orchestration of interneuron migration. The combination of fluorescent labeling and ex/in vivo imaging revealed a cellular highway network within cerebellar cortical layers (the external granular layer, the molecular layer, the Purkinje cell layer, and the internal granular layer). During the first two postnatal weeks, saltatory movements, transient stop phases, cell-cell interaction/contact, and degradation of the extracellular matrix mark out the route of cerebellar interneurons, notably granule cells and basket/stellate cells, to their final location. In addition, cortical-layer specific regulatory factors such as neuropeptides (pituitary adenylate cyclase-activating polypeptide (PACAP), somatostatin) or proteins (tissue-type plasminogen activator (tPA), insulin growth factor-1 (IGF-1)) have been shown to inhibit or stimulate the migratory process of interneurons. These factors show further complexity because somatostatin, PACAP, or tPA have opposite or no effect on interneuron migration depending on which layer or cell type they act upon. External factors originating from environmental conditions (light stimuli, pollutants), nutrients or drug of abuse (alcohol) also alter normal cell migration, leading to cerebellar disorders.
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Affiliation(s)
- Ludovic Galas
- Normandie University, UNIROUEN, INSERM, Regional Cell Imaging Platform of Normandy (PRIMACEN), 76000 Rouen, France.
| | - Magalie Bénard
- Normandie University, UNIROUEN, INSERM, Regional Cell Imaging Platform of Normandy (PRIMACEN), 76000 Rouen, France.
| | - Alexis Lebon
- Normandie University, UNIROUEN, INSERM, Regional Cell Imaging Platform of Normandy (PRIMACEN), 76000 Rouen, France.
| | - Yutaro Komuro
- Department of Neurophysiology, Donders Centre for Neuroscience, Radboud University, Nijmegen 6525 AJ, The Netherlands.
| | - Damien Schapman
- Normandie University, UNIROUEN, INSERM, Regional Cell Imaging Platform of Normandy (PRIMACEN), 76000 Rouen, France.
| | - Hubert Vaudry
- Normandie University, UNIROUEN, INSERM, Regional Cell Imaging Platform of Normandy (PRIMACEN), 76000 Rouen, France.
| | - David Vaudry
- Normandie University, UNIROUEN, INSERM, Regional Cell Imaging Platform of Normandy (PRIMACEN), 76000 Rouen, France.
| | - Hitoshi Komuro
- Department of Neuroscience, School of Medicine, Yale University, New Haven, CT 06510, USA.
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15
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Amin FU, Shah SA, Kim MO. Glycine inhibits ethanol-induced oxidative stress, neuroinflammation and apoptotic neurodegeneration in postnatal rat brain. Neurochem Int 2016; 96:1-12. [DOI: 10.1016/j.neuint.2016.04.001] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2015] [Revised: 03/31/2016] [Accepted: 04/01/2016] [Indexed: 12/22/2022]
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16
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Akita T, Kumada T, Yoshihara SI, Egea J, Yamagishi S. Ion channels, guidance molecules, intracellular signaling and transcription factors regulating nervous and vascular system development. J Physiol Sci 2015; 66:175-88. [PMID: 26507418 PMCID: PMC4752580 DOI: 10.1007/s12576-015-0416-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Accepted: 09/30/2015] [Indexed: 01/13/2023]
Abstract
Our sophisticated thoughts and behaviors are based on the miraculous development of our complex nervous network system, in which many different types of proteins and signaling cascades are regulated in a temporally and spatially ordered manner. Here we review our recent attempts to grasp the principles of nervous system development in terms of general cellular phenomena and molecules, such as volume-regulated anion channels, intracellular Ca2+ and cyclic nucleotide signaling, the Npas4 transcription factor and the FLRT family of axon guidance molecules. We also present an example illustrating that the same FLRT family may regulate the development of vascular networks as well. The aim of this review is to open up new vistas for understanding the intricacy of nervous and vascular system development.
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Affiliation(s)
- Tenpei Akita
- Department of Neurophysiology, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu, Shizuoka, 431-3192, Japan.
| | - Tatsuro Kumada
- Department of Occupational Therapy, Faculty of Health and Medical Sciences, Tokoha University, 1230 Miyakoda-cho, Kita-ku, Hamamatsu, Shizuoka, 431-2102, Japan
| | - Sei-ichi Yoshihara
- Laboratory for Molecular Biology of Neural System, Advanced Medical Research Center, Nara Medical University, 840 Shijo-cho, Kashihara, Nara, 634-8521, Japan
| | - Joaquim Egea
- Molecular and Developmental Neurobiology Group, Biomedical Research Institute of Lleida (IRBLleida), University of Lleida, 25198, Lleida, Spain
| | - Satoru Yamagishi
- Department of Anatomy and Neuroscience, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu, Shizuoka, 431-3192, Japan
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17
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Luhmann HJ, Fukuda A, Kilb W. Control of cortical neuronal migration by glutamate and GABA. Front Cell Neurosci 2015; 9:4. [PMID: 25688185 PMCID: PMC4311642 DOI: 10.3389/fncel.2015.00004] [Citation(s) in RCA: 95] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2014] [Accepted: 01/06/2015] [Indexed: 11/13/2022] Open
Abstract
Neuronal migration in the cortex is controlled by the paracrine action of the classical neurotransmitters glutamate and GABA. Glutamate controls radial migration of pyramidal neurons by acting primarily on NMDA receptors and regulates tangential migration of inhibitory interneurons by activating non-NMDA and NMDA receptors. GABA, acting on ionotropic GABAA-rho and GABAA receptors, has a dichotomic action on radially migrating neurons by acting as a GO signal in lower layers and as a STOP signal in upper cortical plate (CP), respectively. Metabotropic GABAB receptors promote radial migration into the CP and tangential migration of interneurons. Besides GABA, the endogenous GABAergic agonist taurine is a relevant agonist controlling radial migration. To a smaller extent glycine receptor activation can also influence radial and tangential migration. Activation of glutamate and GABA receptors causes increases in intracellular Ca(2+) transients, which promote neuronal migration by acting on the cytoskeleton. Pharmacological or genetic manipulation of glutamate or GABA receptors during early corticogenesis induce heterotopic cell clusters in upper layers and loss of cortical lamination, i.e., neuronal migration disorders which can be associated with neurological or neuropsychiatric diseases. The pivotal role of NMDA and ionotropic GABA receptors in cortical neuronal migration is of major clinical relevance, since a number of drugs acting on these receptors (e.g., anti-epileptics, anesthetics, alcohol) may disturb the normal migration pattern when present during early corticogenesis.
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Affiliation(s)
- Heiko J Luhmann
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University Mainz, Germany
| | - A Fukuda
- Department of Neurophysiology, Hamamatsu University School of Medicine Hamamatsu, Shizuoka, Japan
| | - W Kilb
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University Mainz, Germany
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18
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Marzban H, Del Bigio MR, Alizadeh J, Ghavami S, Zachariah RM, Rastegar M. Cellular commitment in the developing cerebellum. Front Cell Neurosci 2015; 8:450. [PMID: 25628535 PMCID: PMC4290586 DOI: 10.3389/fncel.2014.00450] [Citation(s) in RCA: 94] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2014] [Accepted: 12/12/2014] [Indexed: 12/11/2022] Open
Abstract
The mammalian cerebellum is located in the posterior cranial fossa and is critical for motor coordination and non-motor functions including cognitive and emotional processes. The anatomical structure of cerebellum is distinct with a three-layered cortex. During development, neurogenesis and fate decisions of cerebellar primordium cells are orchestrated through tightly controlled molecular events involving multiple genetic pathways. In this review, we will highlight the anatomical structure of human and mouse cerebellum, the cellular composition of developing cerebellum, and the underlying gene expression programs involved in cell fate commitments in the cerebellum. A critical evaluation of the cell death literature suggests that apoptosis occurs in ~5% of cerebellar cells, most shortly after mitosis. Apoptosis and cellular autophagy likely play significant roles in cerebellar development, we provide a comprehensive discussion of their role in cerebellar development and organization. We also address the possible function of unfolded protein response in regulation of cerebellar neurogenesis. We discuss recent advancements in understanding the epigenetic signature of cerebellar compartments and possible connections between DNA methylation, microRNAs and cerebellar neurodegeneration. Finally, we discuss genetic diseases associated with cerebellar dysfunction and their role in the aging cerebellum.
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Affiliation(s)
- Hassan Marzban
- Department of Human Anatomy and Cell Science, University of Manitoba Winnipeg, MB, Canada
| | - Marc R Del Bigio
- Department of Human Anatomy and Cell Science, University of Manitoba Winnipeg, MB, Canada ; Department of Pathology, University of Manitoba Winnipeg, MB, Canada
| | - Javad Alizadeh
- Department of Human Anatomy and Cell Science, University of Manitoba Winnipeg, MB, Canada
| | - Saeid Ghavami
- Department of Human Anatomy and Cell Science, University of Manitoba Winnipeg, MB, Canada
| | - Robby M Zachariah
- Department of Biochemistry and Medical Genetics, University of Manitoba Winnipeg, MB, Canada ; Regenerative Medicine Program, University of Manitoba Winnipeg, MB, Canada
| | - Mojgan Rastegar
- Department of Biochemistry and Medical Genetics, University of Manitoba Winnipeg, MB, Canada ; Regenerative Medicine Program, University of Manitoba Winnipeg, MB, Canada
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19
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Komuro Y, Galas L, Lebon A, Raoult E, Fahrion JK, Tilot A, Kumada T, Ohno N, Vaudry D, Komuro H. The role of calcium and cyclic nucleotide signaling in cerebellar granule cell migration under normal and pathological conditions. Dev Neurobiol 2014; 75:369-87. [PMID: 25066767 DOI: 10.1002/dneu.22219] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2014] [Revised: 06/30/2014] [Accepted: 07/25/2014] [Indexed: 11/07/2022]
Abstract
In the developing brain, immature neurons migrate from their sites of origin to their final destination, where they reside for the rest of their lives. This active movement of immature neurons is essential for the formation of normal neuronal cytoarchitecture and proper differentiation. Deficits in migration result in the abnormal development of the brain, leading to a variety of neurological disorders. A myriad of extracellular guidance molecules and intracellular effector molecules is involved in controlling the migration of immature neurons in a cell type, cortical layer and birth-date-specific manner. To date, little is known about how extracellular guidance molecules transfer their information to the intracellular effector molecules, which regulate the migration of immature neurons. In this article, to fill the gap between extracellular guidance molecules and intracellular effector molecules, using the migration of cerebellar granule cells as a model system of neuronal cell migration, we explore the role of second messenger signaling (specifically Ca(2+) and cyclic nucleotide signaling) in the regulation of neuronal cell migration. We will, first, describe the cortical layer-specific changes in granule cell migration. Second, we will discuss the roles of Ca(2+) and cyclic nucleotide signaling in controlling granule cell migration. Third, we will present recent studies showing the roles of Ca(2+) and cyclic nucleotide signaling in the deficits in granule cell migration in mouse models of fetal alcohol spectrum disorders and fetal Minamata disease.
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Affiliation(s)
- Yutaro Komuro
- Department of Neurosciences, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, Ohio, 44195
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20
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Ullah N, Naseer MI, Ullah I, Kim TH, Lee HY, Kim MO. Neuroprotective profile of pyruvate against ethanol-induced neurodegeneration in developing mice brain. Neurol Sci 2013; 34:2137-43. [PMID: 23494720 DOI: 10.1007/s10072-013-1350-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2012] [Accepted: 02/28/2013] [Indexed: 11/26/2022]
Abstract
Exposure to ethanol during developmental stages leads to several types of neurological disorders. Apoptotic neurodegeneration due to ethanol exposure is a main feature in alcoholism. Exposure of developing animals to alcohol induces apoptotic neuronal death and causes fetal alcohol syndrome. In the present study, we observed the possible protective effect of pyruvate against ethanol-induced neurodegeneration. Exposure of developing mice to ethanol (2.5 g/kg) induces apoptotic neurodegeneration and widespread neuronal cell death in the cortex and thalamus. Co-treatment of pyruvate (500 mg/kg) protects neuronal cell against ethanol by the reduced expression of caspase-3 in these brain regions. Immunohistochemical analysis and TUNNEL at 24 h showed that apoptotic cell death induced by ethanol in the cortex and thalamus is reduced by pyruvate. Histomorphological analysis at 24 h with cresyl violet staining also proved that pyruvate reduced the number of neuronal cell loss in the cortex and thalamus. The results showed that ethanol increased the expression of caspase-3 and thus induced apoptotic neurodegeneration in the developing mice cortex and thalamus, while co-treatment of pyruvate inhibits the induction of caspase-3 and reduced the cell death in these brain regions. These findings, therefore, showed that treatment of pyruvate inhibits ethanol-induced neuronal cell loss in the postnatal seven (P7) developing mice brain and may appear as a safe neuroprotectant for treating neurodegenerative disorders in newborns and infants.
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Affiliation(s)
- Najeeb Ullah
- Division of Life Science, College of Natural Sciences (RINS) and Applied Life Science, Gyeongsang National University, Chinju, 660-701, Republic of Korea
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21
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Ethanol neurotoxicity in the developing cerebellum: underlying mechanisms and implications. Brain Sci 2013; 3:941-63. [PMID: 24961432 PMCID: PMC4061865 DOI: 10.3390/brainsci3020941] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2013] [Revised: 05/08/2013] [Accepted: 06/04/2013] [Indexed: 01/18/2023] Open
Abstract
Ethanol is the main constituent of alcoholic beverages that exerts toxicity to neuronal development. Ethanol affects synaptogenesis and prevents proper brain development. In humans, synaptogenesis takes place during the third trimester of pregnancy, and in rodents this period corresponds to the initial few weeks of postnatal development. In this period neuronal maturation and differentiation begin and neuronal cells start migrating to their ultimate destinations. Although the neuronal development of all areas of the brain is affected, the cerebellum and cerebellar neurons are more susceptible to the damaging effects of ethanol. Ethanol’s harmful effects include neuronal cell death, impaired differentiation, reduction of neuronal numbers, and weakening of neuronal plasticity. Neuronal development requires many hormones and growth factors such as retinoic acid, nerve growth factors, and cytokines. These factors regulate development and differentiation of neurons by acting through various receptors and their signaling pathways. Ethanol exposure during development impairs neuronal signaling mechanisms mediated by the N-methyl-d-aspartate (NMDA) receptors, the retinoic acid receptors, and by growth factors such as brain-derived neurotrophic factor (BDNF), insulin-like growth factor 1 (IGF-I), and basic fibroblast growth factor (bFGF). In combination, these ethanol effects disrupt cellular homeostasis, reduce the survival and migration of neurons, and lead to various developmental defects in the brain. Here we review the signaling mechanisms that are required for proper neuronal development, and how these processes are impaired by ethanol resulting in harmful consequences to brain development.
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22
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Helfer JL, White ER, Christie BR. Enhanced deficits in long-term potentiation in the adult dentate gyrus with 2nd trimester ethanol consumption. PLoS One 2012; 7:e51344. [PMID: 23227262 PMCID: PMC3515437 DOI: 10.1371/journal.pone.0051344] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2012] [Accepted: 11/05/2012] [Indexed: 12/05/2022] Open
Abstract
Ethanol exposure during pregnancy can cause structural and functional changes in the brain that can impair cognitive capacity. The hippocampal formation, an area of the brain strongly linked with learning and memory, is particularly vulnerable to the teratogenic effects of ethanol. In the present experiments we sought to determine if the functional effects of developmental ethanol exposure could be linked to ethanol exposure during any single trimester-equivalent. Ethanol exposure during the 1st or 3rd trimester-equivalent produced only minor changes in synaptic plasticity in adult offspring. In contrast, ethanol exposure during the 2nd trimester equivalent resulted in a pronounced decrease in long-term potentiation, indicating that the timing of exposure influences the severity of the deficit. Together, the results from these experiments demonstrate long-lasting alterations in synaptic plasticity as the result of developmental ethanol exposure and dependent on the timing of exposure. Furthermore, these results allude to neural circuit malfunction within the hippocampal formation, perhaps relating to the learning and memory deficits observed in individuals with fetal alcohol spectrum disorders.
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Affiliation(s)
- Jennifer L. Helfer
- Division of Medical Sciences, University of Victoria, Victoria, British Columbia, Canada
- Department of Biology, University of Victoria, Victoria, British Columbia, Canada
| | - Emily R. White
- Division of Medical Sciences, University of Victoria, Victoria, British Columbia, Canada
- Graduate Program in Neuroscience, University of Victoria, Victoria, British Columbia, Canada
| | - Brian R. Christie
- Division of Medical Sciences, University of Victoria, Victoria, British Columbia, Canada
- Department of Biology, University of Victoria, Victoria, British Columbia, Canada
- Graduate Program in Neuroscience, University of Victoria, Victoria, British Columbia, Canada
- Graduate Program in Neuroscience and the Department of Cellular and Physiological Sciences, University of British Columbia, Vancouver, British Columbia, Canada
- The Brain Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
- * E-mail:
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23
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Manent JB, Beguin S, Ganay T, Represa A. Cell-autonomous and cell-to-cell signalling events in normal and altered neuronal migration. Eur J Neurosci 2012; 34:1595-608. [PMID: 22103417 DOI: 10.1111/j.1460-9568.2011.07867.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The cerebral cortex is a complex six-layered structure that contains an important diversity of neurons, and has rich local and extrinsic connectivity. Among the mechanisms governing the cerebral cortex construction, neuronal migration is perhaps the most crucial as it ensures the timely formation of specific and selective neuronal circuits. Here, we review the main extrinsic and extrinsic factors involved in regulating neuronal migration in the cortex and describe some environmental factors interfering with their actions.
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24
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Rescue of neuronal migration deficits in a mouse model of fetal Minamata disease by increasing neuronal Ca2+ spike frequency. Proc Natl Acad Sci U S A 2012; 109:5057-62. [PMID: 22411806 DOI: 10.1073/pnas.1120747109] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
In the brains of patients with fetal Minamata disease (FMD), which is caused by exposure to methylmercury (MeHg) during development, many neurons are hypoplastic, ectopic, and disoriented, indicating disrupted migration, maturation, and growth. MeHg affects a myriad of signaling molecules, but little is known about which signals are primary targets for MeHg-induced deficits in neuronal development. In this study, using a mouse model of FMD, we examined how MeHg affects the migration of cerebellar granule cells during early postnatal development. The cerebellum is one of the most susceptible brain regions to MeHg exposure, and profound loss of cerebellar granule cells is detected in the brains of patients with FMD. We show that MeHg inhibits granule cell migration by reducing the frequency of somal Ca(2+) spikes through alterations in Ca(2+), cAMP, and insulin-like growth factor 1 (IGF1) signaling. First, MeHg slows the speed of granule cell migration in a dose-dependent manner, independent of the mode of migration. Second, MeHg reduces the frequency of spontaneous Ca(2+) spikes in granule cell somata in a dose-dependent manner. Third, a unique in vivo live-imaging system for cell migration reveals that reducing the inhibitory effects of MeHg on somal Ca(2+) spike frequency by stimulating internal Ca(2+) release and Ca(2+) influxes, inhibiting cAMP activity, or activating IGF1 receptors ameliorates the inhibitory effects of MeHg on granule cell migration. These results suggest that alteration of Ca(2+) spike frequency and Ca(2+), cAMP, and IGF1 signaling could be potential therapeutic targets for infants with MeHg intoxication.
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25
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Ullah N, Naseer MI, Ullah I, Lee HY, Koh PO, Kim MO. Protective effect of pyruvate against ethanol-induced apoptotic neurodegeneration in the developing rat brain. Neuropharmacology 2011; 61:1248-55. [DOI: 10.1016/j.neuropharm.2011.06.031] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2010] [Revised: 06/07/2011] [Accepted: 06/21/2011] [Indexed: 10/18/2022]
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26
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Cytoarchitectonic and neurochemical differentiation of the visual system in ethanol-induced cyclopic zebrafish larvae. Neurotoxicol Teratol 2011; 33:686-97. [DOI: 10.1016/j.ntt.2011.06.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2011] [Revised: 05/20/2011] [Accepted: 06/05/2011] [Indexed: 11/24/2022]
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27
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Riccio O, Jacobshagen M, Golding B, Vutskits L, Jabaudon D, Hornung JP, Dayer AG. Excess of serotonin affects neocortical pyramidal neuron migration. Transl Psychiatry 2011; 1:e47. [PMID: 22833193 PMCID: PMC3309486 DOI: 10.1038/tp.2011.49] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
The serotonin transporter (SERT) is a key molecule involved in the homeostasis of extracellular levels of serotonin and is regulated developmentally. Genetic deletion of SERT in rodents increases extracellular levels of serotonin and affects cellular processes involved in neocortical circuit assembly such as barrel cortex wiring and cortical interneuron migration. Importantly, pharmacological blockade of SERT during brain development leads to phenotypes relevant to psychiatry in rodents and to an increased risk for autism spectrum disorders in humans. Furthermore, developmental adversity interacts with genetically-driven variations of serotonin function in humans and nonhuman primates to increase the risk for a variety of stress-related phenotypes. In this study, we investigate whether an excess of serotonin affects the migration of neocortical pyramidal neurons during development. Using in utero electroporation combined with time-lapse imaging to specifically monitor pyramidal neurons during late mouse embryogenesis, we show that an excess of serotonin reversibly affects the radial migration of pyramidal neurons. We further identify that the serotonin receptor 5-HT(6) is expressed in pyramidal neuron progenitors and that 5-HT(6) receptor activation replicates the effects of serotonin stimulation. Finally, we show that the positioning of superficial layer pyramidal neurons is altered in vivo in SERT knockout mice. Taken together, these results indicate that a developmental excess of serotonin decreases the migration speed of cortical pyramidal neurons, affecting a fundamental step in the assembly of neural circuits. These findings support the hypothesis that developmental dysregulation of serotonin homeostasis has detrimental effects on neocortical circuit formation and contributes to increased vulnerability to psychiatric disorders.
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Affiliation(s)
- O Riccio
- Department of Mental Health and Psychiatry, University Hospital of Geneva, Geneva, Switzerland,Department of Basic Neurosciences, University of Geneva Medical School, Geneva, Switzerland,Geneva Neuroscience Center, University of Geneva Medical School, Geneva, Switzerland
| | - M Jacobshagen
- Department of Mental Health and Psychiatry, University Hospital of Geneva, Geneva, Switzerland,Department of Basic Neurosciences, University of Geneva Medical School, Geneva, Switzerland,Geneva Neuroscience Center, University of Geneva Medical School, Geneva, Switzerland
| | - B Golding
- Department of Basic Neurosciences, University of Geneva Medical School, Geneva, Switzerland,Geneva Neuroscience Center, University of Geneva Medical School, Geneva, Switzerland
| | - L Vutskits
- Department of Basic Neurosciences, University of Geneva Medical School, Geneva, Switzerland,Geneva Neuroscience Center, University of Geneva Medical School, Geneva, Switzerland,Department of Anesthesiology Pharmacology and Intensive Care, University Hospital of Geneva, Geneva, Switzerland
| | - D Jabaudon
- Department of Basic Neurosciences, University of Geneva Medical School, Geneva, Switzerland,Geneva Neuroscience Center, University of Geneva Medical School, Geneva, Switzerland,Clinic of Neurology, University Hospital of Geneva, Geneva, Switzerland
| | - J P Hornung
- Department of Cellular Biology and Morphology, University of Lausanne, Lausanne, Switzerland
| | - A G Dayer
- Department of Mental Health and Psychiatry, University Hospital of Geneva, Geneva, Switzerland,Department of Basic Neurosciences, University of Geneva Medical School, Geneva, Switzerland,Geneva Neuroscience Center, University of Geneva Medical School, Geneva, Switzerland,Department of Mental Health and General Psychiatry, University Geneva Medical Center (CMU), Rue Michel-Servet 1, 1211 Genève 4, Switzerland. E-mail:
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28
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Myelination and axonal electrical activity modulate the distribution and motility of mitochondria at CNS nodes of Ranvier. J Neurosci 2011; 31:7249-58. [PMID: 21593309 DOI: 10.1523/jneurosci.0095-11.2011] [Citation(s) in RCA: 139] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Energy production presents a formidable challenge to axons as their mitochondria are synthesized and degraded in neuronal cell bodies. To meet the energy demands of nerve conduction, small mitochondria are transported to and enriched at mitochondrial stationary sites located throughout the axon. In this study, we investigated whether size and motility of mitochondria in small myelinated CNS axons are differentially regulated at nodes, and whether mitochondrial distribution and motility are modulated by axonal electrical activity. The size/volume of mitochondrial stationary sites was significantly larger in juxtaparanodal/internodal axoplasm than in nodal/paranodal axoplasm. With three-dimensional electron microscopy, we observed that axonal mitochondrial stationary sites were composed of multiple mitochondria of varying length, except at nodes where mitochondria were uniformly short and frequently absent altogether. Mitochondrial transport speed was significantly reduced in nodal axoplasm compared with internodal axoplasm. Increased axonal electrical activity decreased mitochondrial transport and increased the size of mitochondrial stationary sites in nodal/paranodal axoplasm. Decreased axonal electrical activity had the opposite effect. In cerebellar axons of the myelin-deficient rat, which contain voltage-gated Na(+) channel clusters but lack paranodal specializations, axonal mitochondrial motility and stationary site size were similar at Na(+) channel clusters and other axonal regions. These results demonstrate juxtaparanodal/internodal enrichment of stationary mitochondria and neuronal activity-dependent dynamic modulation of mitochondrial distribution and transport in nodal axoplasm. In addition, the modulation of mitochondrial distribution and motility requires oligodendrocyte-axon interactions at paranodal specializations.
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29
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Trophic and proliferative perturbations of in vivo/in vitro cephalic neural crest cells after ethanol exposure are prevented by Neurotrophin 3. Neurotoxicol Teratol 2011; 33:422-30. [DOI: 10.1016/j.ntt.2011.03.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2010] [Revised: 12/23/2010] [Accepted: 03/15/2011] [Indexed: 01/27/2023]
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30
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Brocardo PS, Gil-Mohapel J, Christie BR. The role of oxidative stress in fetal alcohol spectrum disorders. ACTA ACUST UNITED AC 2011; 67:209-25. [PMID: 21315761 DOI: 10.1016/j.brainresrev.2011.02.001] [Citation(s) in RCA: 93] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2010] [Revised: 02/02/2011] [Accepted: 02/03/2011] [Indexed: 10/18/2022]
Abstract
The ingestion of alcohol/ethanol during pregnancy can result in abnormal fetal development in both humans and a variety of experimental animal models. Depending on the pattern of consumption, the dose, and the period of exposure to ethanol, a myriad of structural and functional deficits can be observed. These teratogenic effects are thought to result from the ethanol-induced dysregulation of a variety of intracellular pathways ultimately culminating in toxicity and cell death. For instance, ethanol exposure can lead to the generation of reactive oxygen species (ROS) and produce an imbalance in the intracellular redox state, leading to an overall increase in oxidative stress. In the present review we will provide an up-to-date summary on the effects of prenatal/neonatal ethanol exposure on the levels of oxidative stress in the central nervous system (CNS) of experimental models of fetal alcohol spectrum disorders (FASD). We will also review the evidence for the use of antioxidants as potential therapeutic strategies for the treatment of some of the neuropathological deficits characteristic of both rodent models of FASD and children afflicted with these disorders. We conclude that an imbalance in the intracellular redox state contributes to the deficits seen in FASD and suggest that antioxidants are potential candidates for the development of novel therapeutic strategies for the treatment of these developmental disorders.
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Affiliation(s)
- Patricia S Brocardo
- Division of Medical Sciences, University of Victoria, Victoria, BC, V8W 2Y2, Canada
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Kumada T, Komuro Y, Li Y, Hu T, Wang Z, Littner Y, Komuro H. Inhibition of cerebellar granule cell turning by alcohol. Neuroscience 2010; 170:1328-44. [PMID: 20691765 PMCID: PMC2949482 DOI: 10.1016/j.neuroscience.2010.07.059] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2010] [Revised: 06/30/2010] [Accepted: 07/29/2010] [Indexed: 01/24/2023]
Abstract
Ectopic neurons are often found in the brains of fetal alcohol spectrum disorders (FASD) and fetal alcohol syndrome (FAS) patients, suggesting that alcohol exposure impairs neuronal cell migration. Although it has been reported that alcohol decreases the speed of neuronal cell migration, little is known about whether alcohol also affects the turning of neurons. Here we show that ethanol exposure inhibits the turning of cerebellar granule cells in vivo and in vitro. First, in vivo studies using P10 mice demonstrated that a single intraperitoneal injection of ethanol not only reduces the number of turning granule cells but also alters the mode of turning at the EGL-ML border of the cerebellum. Second, in vitro analysis using microexplant cultures of P0-P3 mouse cerebella revealed that ethanol directly reduces the frequency of spontaneous granule cell turning in a dose-dependent manner. Third, the action of ethanol on the frequency of granule cell turning was significantly ameliorated by stimulating Ca(2+) and cGMP signaling or by inhibiting cAMP signaling. Taken together, these results indicate that ethanol affects the frequency and mode of cerebellar granule cell turning through alteration of the Ca(2+) and cyclic nucleotide signaling pathways, suggesting that the abnormal allocation of neurons found in the brains of FASD and FSA patients results, at least in part, from impaired turning of immature neurons by alcohol.
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Affiliation(s)
- T Kumada
- Department of Neurosciences, Lerner Research Institute, The Cleveland Clinic Foundation, Cleveland, OH 44195, USA
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32
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Pueta M, Rovasio RA, Abate P, Spear NE, Molina JC. Prenatal and postnatal ethanol experiences modulate consumption of the drug in rat pups, without impairment in the granular cell layer of the main olfactory bulb. Physiol Behav 2010; 102:63-75. [PMID: 20951715 DOI: 10.1016/j.physbeh.2010.10.009] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2010] [Revised: 10/05/2010] [Accepted: 10/11/2010] [Indexed: 10/18/2022]
Abstract
The effect of moderate exposure to ethanol during late gestation was studied in terms of its interaction with moderate exposure during nursing from an intoxicated dam. A further issue was whether behavioral effects of ethanol, especially the enhanced ethanol intake known to occur after moderate ethanol prenatally or during nursing, depend upon teratological effects that may include death of neurons in the main olfactory bulb (MOB). During gestational days 17-20 rats were given 0, 1 or 2g/kg ethanol doses intragastrically (i.g.). After parturition these dams were given a dose of 2.5g/kg ethanol i.g. each day and allowed to perform regular nursing activities. During postnatal days (PDs) 15 and 16, ethanol intake of pups was assessed along with aspects of their general activity. In a second experiment pups given the same prenatal treatment as above were tested for blood ethanol concentration (BEC) in response to an ethanol challenge on PD6. A third experiment (Experiment 2b) assessed stereologically the number of cells in the granular cell layer of the MOB on PD7, as a function of analogous pre- and postnatal ethanol exposures. Results revealed that ethanol intake during the third postnatal week was increased by prenatal as well as postnatal ethanol exposure, with a few interesting qualifications. For instance, pups given 1g/kg prenatally did not have increased ethanol intake unless they also had experienced ethanol during nursing. There were no effects of ethanol on either BECs or conventional teratology (cell number). This increases the viability of an explanation of the effects of prenatal and early postnatal ethanol on later ethanol intake in terms of learning and memory.
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Affiliation(s)
- Mariana Pueta
- Instituto de Investigación Médica M. y M. Ferreyra (INIMEC-CONICET), Córdoba, C.P 5016, Argentina.
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33
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Novel adenosine and cAMP signalling pathways in migrating glial cells. Cell Calcium 2010; 48:83-90. [PMID: 20688392 DOI: 10.1016/j.ceca.2010.07.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2010] [Revised: 07/08/2010] [Accepted: 07/09/2010] [Indexed: 11/22/2022]
Abstract
This study was aimed at characterizing the effect of purinergic transmission on migration of embryonic ciliary ganglion satellite glial cells. Application of adenosine significantly decreased the rate of migration of glial cells whereas no differences were observed in the presence of ATP. The A(2B) receptor antagonist reverted this action, but application of an A(2A) receptor antagonist or a cAMP-protein kinase inhibitor had no effect on the agonist's stimulation. Forskolin, which stimulates adenylate cyclase activity, and the cAMP analogue 8-CPT-2'-O-Me-cAMP, which selectively activates the guanine exchange factor Epac1, mimicked the effect of adenosine. In addition, intracellular calcium measurements studies revealed that application of either adenosine or ATP induced an increase in [Ca(2+)]i and that the adenosine-induced [Ca(2+)]i response was due to Ca(2+) entry and was blocked by an A(2A) receptor antagonist, SCH 58261, or by high Gd(3+) concentrations. Furthermore, forskolin, but not 8-CPT-2'-O-Me-cAMP, activated the Ca(2+) entry which was blocked by Gd(3+) and was independent of cAMP-protein kinase activity. These results demonstrate the involvement of purinergic P1 signalling in the regulation of cellular migration, and point to the importance of adenosine as a negative modulator of migration of peripheral developing glial cells and as an activator of Ca(2+) entry.
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Diversity of lysophosphatidic acid receptor-mediated intracellular calcium signaling in early cortical neurogenesis. J Neurosci 2010; 30:7300-9. [PMID: 20505096 DOI: 10.1523/jneurosci.6151-09.2010] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Lysophosphatidic acid (LPA) is a membrane-derived lysophospholipid that can induce pleomorphic effects in neural progenitor cells (NPCs) from the cerebral cortex, including alterations in ionic conductance. LPA-induced, calcium-mediated conductance changes have been reported; however, the underlying molecular mechanisms have not been determined. We show here that activation of specific cognate receptors accounts for nearly all intracellular calcium responses evoked by LPA in acutely cultured nestin-positive NPCs from the developing mouse cerebral cortex. Fast-onset changes in intracellular calcium levels required release from thapsigargin-sensitive stores by a pertussis toxin-insensitive mechanism. The influx of extracellular calcium through Cd(2+)/Ni(2+)-insensitive influx pathways, approximately one-half of which were Gd(3+) sensitive, contributed to the temporal diversity of responses. Quantitative reverse transcription-PCR revealed the presence of all five known LPA receptors in primary NPCs, with prominent expression of LPA(1), LPA(2), and LPA(4). Combined genetic and pharmacological studies indicated that NPC responses were mediated by LPA(1) (approximately 30% of the cells), LPA(2) (approximately 30%), a combination of receptors on single cells (approximately 30%), and non-LPA(1,2,3) pathways (approximately 10%). LPA responsivity was significantly reduced in more differentiated TuJ1(+) cells within cultures. Calcium transients in a large proportion of LPA-responsive NPCs were also initiated by the closely related signaling lipid S1P (sphingosine-1-phosphate). These data demonstrate for the first time the involvement of LPA receptors in mediating surprisingly diverse NPC calcium responses involving multiple receptor subtypes that function within a single cell. Compared with other known factors, lysophospholipids represent the major activator of calcium signaling identified within NPCs at this early stage in corticogenesis.
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Demyelination increases axonal stationary mitochondrial size and the speed of axonal mitochondrial transport. J Neurosci 2010; 30:6658-66. [PMID: 20463228 DOI: 10.1523/jneurosci.5265-09.2010] [Citation(s) in RCA: 127] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Axonal degeneration contributes to permanent neurological disability in inherited and acquired diseases of myelin. Mitochondrial dysfunction has been proposed as a major contributor to this axonal degeneration. It remains to be determined, however, if myelination, demyelination, or remyelination alter the size and distribution of axonal mitochondrial stationary sites or the rates of axonal mitochondrial transport. Using live myelinated rat dorsal root ganglion (DRG) cultures, we investigated whether myelination and lysolecithin-induced demyelination affect axonal mitochondria. Myelination increased the size of axonal stationary mitochondrial sites by 2.3-fold. After demyelination, the size of axonal stationary mitochondrial sites was increased by an additional 2.2-fold and the transport velocity of motile mitochondria was increased by 47%. These measures returned to the levels of myelinated axons after remyelination. Demyelination induced activating transcription factor 3 (ATF3) in DRG neurons. Knockdown of neuronal ATF3 by short hairpin RNA abolished the demyelination-induced increase in axonal mitochondrial transport and increased nitrotyrosine immunoreactivity in axonal mitochondria, suggesting that neuronal ATF3 expression and increased mitochondrial transport protect demyelinated axons from oxidative damage. In response to insufficient ATP production, demyelinated axons increase the size of stationary mitochondrial sites and thereby balance ATP production with the increased energy needs of nerve conduction.
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Guo D, Zhang JJ, Huang XY. A new Rac/PAK/GC/cGMP signaling pathway. Mol Cell Biochem 2009; 334:99-103. [PMID: 19937092 DOI: 10.1007/s11010-009-0327-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2009] [Accepted: 11/04/2009] [Indexed: 10/20/2022]
Abstract
Guanosine 3',5'-cyclic monophosphate (cGMP) and small GTPase Rac are critical regulators of cell functions. Recently, Rac has been shown to use its downstream effector p21-activated kinase (PAK) to directly activate transmembrane guanylyl cyclases (GCs). This novel Rac/PAK/GC/cGMP signaling pathway bridges Rac and cGMP, and provides a general molecular mechanism for diverse receptors to regulate physiological functions such as cell migration through elevating the cellular cGMP level.
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Affiliation(s)
- Dagang Guo
- Department of Physiology, Cornell University Weill Medical College, New York, NY 10065, USA
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37
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Role of PACAP in Controlling Granule Cell Migration. THE CEREBELLUM 2009; 8:433-40. [DOI: 10.1007/s12311-009-0121-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/24/2008] [Accepted: 06/01/2009] [Indexed: 11/26/2022]
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Cameron DB, Kasai K, Jiang Y, Hu T, Saeki Y, Komuro H. Four distinct phases of basket/stellate cell migration after entering their final destination (the molecular layer) in the developing cerebellum. Dev Biol 2009; 332:309-24. [PMID: 19500566 DOI: 10.1016/j.ydbio.2009.05.575] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2009] [Revised: 05/28/2009] [Accepted: 05/29/2009] [Indexed: 12/20/2022]
Abstract
In the adult cerebellum, basket/stellate cells are scattered throughout the ML, but little is known about the process underlying the cell dispersion. To determine the allocation of stellate/basket cells within the ML, we examined their migration in the early postnatal mouse cerebellum. We found that after entering the ML, basket/stellate cells sequentially exhibit four distinct phases of migration. First, the cells migrated radially from the bottom to the top while exhibiting saltatory movement with a single leading process (Phase I). Second, the cells turned at the top and migrated tangentially in a rostro-caudal direction, with an occasional reversal of the direction of migration (Phase II). Third, the cells turned and migrated radially within the ML at a significantly reduced speed while repeatedly extending and withdrawing the leading processes (Phase III). Fourth, the cells turned at the middle and migrated tangentially at their slowest speed, while extending several dendrite-like processes after having completely withdrawn the leading process (Phase IV). Finally, the cells stopped and completed their migration. These results suggest that the dispersion of basket/stellate cells in the ML is controlled by the orchestrated activity of external guidance cues, cell-cell contact and intrinsic programs in a position- and time-dependent manner.
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Affiliation(s)
- D Bryant Cameron
- Department of Neurosciences/NC30, Lerner Research Institute, The Cleveland Clinic Foundation, Cleveland, OH 44195, USA
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39
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Excess of serotonin affects embryonic interneuron migration through activation of the serotonin receptor 6. Mol Psychiatry 2009; 14:280-90. [PMID: 18663366 DOI: 10.1038/mp.2008.89] [Citation(s) in RCA: 109] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The discovery that a common polymorphism (5-HTTLPR, short variant) in the human serotonin transporter gene (SLC6A4) can influence personality traits and increase the risk for depression in adulthood has led to the hypothesis that a relative increase in the extracellular levels of serotonin (5-HT) during development could be critical for the establishment of brain circuits. Consistent with this idea, a large body of data demonstrate that 5-HT is a strong neurodevelopmental signal that can modulate a wide variety of cellular processes. In humans, serotonergic fibers appear in the developing cortex as early as the 10th gestational week, a period of intense neuronal migration. In this study we hypothesized that an excess of 5-HT could affect embryonic cortical interneuron migration. Using time-lapse videometry to monitor the migration of interneurons in embryonic mouse cortical slices, we discovered that the application of 5-HT decreased interneuron migration in a reversible and dose-dependent manner. We next found that 5-HT6 receptors were expressed in cortical interneurons and that 5-HT6 receptor activation decreased interneuron migration, whereas 5-HT6 receptor blockade prevented the migratory effects induced by 5-HT. Finally, we observed that interneurons were abnormally distributed in the cerebral cortex of serotonin transporter gene (Slc6a4) knockout mice that have high levels of extracellular 5-HT. These results shed new light on the neurodevelopmental alterations caused by an excess of 5-HT during the embryonic period and contribute to a better understanding of the cellular processes that could be modulated by genetically controlled differences in human 5-HT homeostasis.
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40
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Ben-Ari Y. Neuro-archaeology: pre-symptomatic architecture and signature of neurological disorders. Trends Neurosci 2008; 31:626-36. [DOI: 10.1016/j.tins.2008.09.002] [Citation(s) in RCA: 108] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2008] [Revised: 09/26/2008] [Accepted: 09/26/2008] [Indexed: 01/16/2023]
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41
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Autonomous turning of cerebellar granule cells in vitro by intrinsic programs. Dev Biol 2008; 326:237-49. [PMID: 19063877 DOI: 10.1016/j.ydbio.2008.11.012] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2008] [Revised: 10/05/2008] [Accepted: 11/17/2008] [Indexed: 11/23/2022]
Abstract
External guidance cues play a role in controlling neuronal cell turning in the developing brain, but little is known about whether intrinsic programs are also involved in controlling the turning. In this study, we examined whether granule cells undergo autonomous changes in the direction of migration in the microexplant cultures of the early postnatal mouse cerebellum. We found that granule cells exhibit spontaneous and periodical turning without cell-cell contact and in the absence of external guidance cues. The frequency of turning was increased by stimulating the Ca(2+) influx and the internal Ca(2+) release, or inhibiting the cAMP signaling pathway, while the frequency was reduced by inhibiting the Ca(2+) influx. Granule cell turning in vitro was classified into four distinct modes, which were characterized by the morphological changes in the leading process and the trailing process, such as bifurcating, turning, withdrawing, and changing the polarity. The occurrence of the 1st and 2nd modes of turning was differentially affected by altering the Ca(2+) and cAMP signaling pathways. Collectively, the results demonstrate that intrinsic programs regulate the autonomous turning of cerebellar granule cells in vitro. Furthermore, the results suggest that extrinsic signals play a role as essential modulators of intrinsic programs.
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42
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Jaatinen P, Rintala J. Mechanisms of ethanol-induced degeneration in the developing, mature, and aging cerebellum. THE CEREBELLUM 2008; 7:332-47. [DOI: 10.1007/s12311-008-0034-z] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2007] [Accepted: 08/01/2007] [Indexed: 11/30/2022]
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Jiang Y, Kumada T, Cameron DB, Komuro H. Cerebellar granule cell migration and the effects of alcohol. Dev Neurosci 2008; 30:7-23. [PMID: 18075250 DOI: 10.1159/000109847] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2006] [Accepted: 01/04/2007] [Indexed: 01/30/2023] Open
Abstract
In the developing brain the majority of neurons migrate from their birthplace to their final destination. This active movement is essential for the formation of cortical layers and nuclei. The impairment of migration does not affect the viability of neurons but often results in abnormal differentiation. The proper migration of neurons requires the orchestrated activities of multiple cellular and molecular events, such as pathway selection, the activation of specific receptors and channels, and the assembly and disassembly of cytoskeletal components. The migration of neurons is very vulnerable to exposure to environmental toxins, such as alcohol. In this article, we will focus on recent developments in the migration of cerebellar granule cells. First, we will describe when, where and how granule cells migrate through different cortical layers to reach their final destination. Second, we will present how internal programs control the sequential changes in granule cell migration. Third, we will review the roles of external guidance cues and transmembrane signals in granule cell migration. Finally, we will reveal mechanisms by which alcohol exposure impairs granule cell migration.
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Affiliation(s)
- Yulan Jiang
- Department of Neurosciences, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, Ohio, USA
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Zaninetti R, Tacchi S, Erriquez J, Distasi C, Maggi R, Cariboni A, Condorelli F, Canonico PL, Genazzani AA. Calcineurin primes immature gonadotropin-releasing hormone-secreting neuroendocrine cells for migration. Mol Endocrinol 2007; 22:729-36. [PMID: 18032695 DOI: 10.1210/me.2007-0277] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
During development, many neurons display calcium-dependent migration, but the role of this messenger in regulating gene expression leading to this event has not yet been elucidated. Among the decoders of calcium signals is calcineurin, a Ca(2+)/calmodulin serine/threonine phosphatase that has been involved in both short-term and long-term cellular changes. By using immortalized GnRH-secreting neurons, we now show that, in vitro, Ca(2+)-dependent gene expression, proceeding via calcineurin and the transcription factor nuclear factor of activated T cells, is a key player controlling the chemomigratory potential of developing GnRH-secreting neurons. Furthermore, our data highlight the switch nature of this phosphatase, whose activation or inactivation guides cells to proceed from one genetic program to the next.
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Affiliation(s)
- R Zaninetti
- Dipartimento di Scienze Chimiche, Alimentari, Farmaceutiche e Farmacologiche and Drug and Food Biotechnology Center, Università degli Studi del Piemonte Orientale A. Avogadro, 28100 Novara, Italy
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45
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Lombard Z, Tiffin N, Hofmann O, Bajic VB, Hide W, Ramsay M. Computational selection and prioritization of candidate genes for fetal alcohol syndrome. BMC Genomics 2007; 8:389. [PMID: 17961254 PMCID: PMC2194724 DOI: 10.1186/1471-2164-8-389] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2007] [Accepted: 10/25/2007] [Indexed: 01/07/2023] Open
Abstract
Background Fetal alcohol syndrome (FAS) is a serious global health problem and is observed at high frequencies in certain South African communities. Although in utero alcohol exposure is the primary trigger, there is evidence for genetic- and other susceptibility factors in FAS development. No genome-wide association or linkage studies have been performed for FAS, making computational selection and -prioritization of candidate disease genes an attractive approach. Results 10174 Candidate genes were initially selected from the whole genome using a previously described method, which selects candidate genes according to their expression in disease-affected tissues. Hereafter candidates were prioritized for experimental investigation by investigating criteria pertinent to FAS and binary filtering. 29 Criteria were assessed by mining various database sources to populate criteria-specific gene lists. Candidate genes were then prioritized for experimental investigation using a binary system that assessed the criteria gene lists against the candidate list, and candidate genes were scored accordingly. A group of 87 genes was prioritized as candidates and for future experimental validation. The validity of the binary prioritization method was assessed by investigating the protein-protein interactions, functional enrichment and common promoter element binding sites of the top-ranked genes. Conclusion This analysis highlighted a list of strong candidate genes from the TGF-β, MAPK and Hedgehog signalling pathways, which are all integral to fetal development and potential targets for alcohol's teratogenic effect. We conclude that this novel bioinformatics approach effectively prioritizes credible candidate genes for further experimental analysis.
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Affiliation(s)
- Zané Lombard
- Division of Human Genetics, National Health Laboratory Service & School of Pathology, University of the Witwatersrand, Johannesburg, 2001, South Africa.
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Hassoun AT, Erdélyi F, Szabó G, Davis MI. A rapid screening method for population-specific neuronal motogens, substrates and associated signaling pathways. J Neurosci Methods 2007; 166:178-94. [PMID: 17826844 PMCID: PMC2443863 DOI: 10.1016/j.jneumeth.2007.07.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2007] [Revised: 07/02/2007] [Accepted: 07/07/2007] [Indexed: 11/27/2022]
Abstract
We developed and characterized an assay that allows for rapid examination of migration of specific neuronal populations within a mixed population using the Boyden chamber principle. Migration of cerebellar interneurons and granule cells was examined using mice expressing enhanced green fluorescent protein (eGFP) under the glutamate decarboxylase (GAD(65)) and growth-associated protein-43 (GAP43) promoters, respectively. Brain-derived neurotrophic factor (BDNF) was used as the prototypic motogen for both populations. Fluorescent light-blocking inserts (FluoroBlok) with different pore sizes and densities were compared in a two-compartment assay. Immunodetection of polarity markers and nuclear staining indicated that dendrites and somata are preferentially extended through the pores in response to BDNF. Inserts coated with extracellular matrix (ECM) proteins were used to examine interactions between BDNF and the ECM during migration. ECM proteins alone stimulated migration when the lower side of the insert was coated, however coating of both sides of the insert slowed migration when compared to poly-D-lysine. Addition of a PI 3-kinase inhibitor to the lower compartment blocked BDNF-stimulated migration of both populations while a Src inhibitor reduced laminin-stimulated migration of interneurons, but not granule cells. We also examined use of neurons cultured from GAD(65)-eGFP mice as a reporter system for promoter activity. GAD(65)-eGFP mice may also be useful as a model for promoter regulation and the potential confounding effects of eGFP induction by the stimuli are also addressed. This assay allows for rapid analysis of motogens, substrates and signaling pathways that regulate migration of selected neuronal populations.
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Affiliation(s)
- Amani T Hassoun
- Laboratory for Integrative Neuroscience/Section on Synaptic Pharmacology, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892, USA.
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47
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Liu LY, Hoffman GE, Fei XW, Li Z, Zhang ZH, Mei YA. Delayed rectifier outward K+ current mediates the migration of rat cerebellar granule cells stimulated by melatonin. J Neurochem 2007; 102:333-44. [PMID: 17561939 DOI: 10.1111/j.1471-4159.2007.04669.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Melatonin (MT) may work as a neuromodulator through the associated MT receptors in the central nervous system. Previously, our studies have shown that MT increased the I(K) current via a G protein-related pathway. In the present study, patch-clamp whole-cell recording, transwell migration assays and organotypic cerebellar slice cultures were used to examine the effect of MT on granule cell migration. MT increased the I(K) current amplitude and migration of granule cells. Meanwhile, TEA, the I(K) channel blocker, decreased the I(K) current and slowed the migration of granule cells. Furthermore, the effects of MT on the I(K) current and cell migration were not abolished by pre-incubation with P7791, a specific antagonist of MT(3)R, but were eliminated by the application of the MT(2)R antagonists K185 and 4-P-PDOT. I(K) current and cell migration were decreased by the application of dibutyryl cyclic AMP (dbcAMP), which was in contrast to the MT effect on the I(K) current and cell migration. Incubation with dbcAMP essentially blocked the MT-induced increasing effect. Moreover, incubation of isolated cell cultures in the MT-containing medium also decreased the cAMP immunoreactivity in the granule cells. It is concluded, therefore, that I(K) current, downstream of a cAMP transduction pathway, mediates the migration of rat cerebellar granule cells stimulated by MT.
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MESH Headings
- Animals
- Animals, Newborn
- Bucladesine/pharmacology
- Cell Differentiation/drug effects
- Cell Differentiation/physiology
- Cell Movement/drug effects
- Cell Movement/physiology
- Cells, Cultured
- Cerebellar Cortex/cytology
- Cerebellar Cortex/growth & development
- Cerebellar Cortex/metabolism
- Culture Media, Conditioned/pharmacology
- Cyclic AMP/metabolism
- Melatonin/metabolism
- Melatonin/pharmacology
- Membrane Potentials/drug effects
- Membrane Potentials/physiology
- Models, Neurological
- Neurons/cytology
- Neurons/drug effects
- Neurons/metabolism
- Organ Culture Techniques
- Patch-Clamp Techniques
- Potassium Channel Blockers/pharmacology
- Potassium Channels, Voltage-Gated/drug effects
- Potassium Channels, Voltage-Gated/metabolism
- Rats
- Rats, Sprague-Dawley
- Receptor, Melatonin, MT2/antagonists & inhibitors
- Receptor, Melatonin, MT2/metabolism
- Receptors, Melatonin/antagonists & inhibitors
- Receptors, Melatonin/metabolism
- Signal Transduction/physiology
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Affiliation(s)
- Lin-Yun Liu
- Institutes of Brain Science, School of Life Sciences and State Key Laboratory of Medical Neurobiology, Fudan University, Shanghai, China
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48
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Servais L, Hourez R, Bearzatto B, Gall D, Schiffmann SN, Cheron G. Purkinje cell dysfunction and alteration of long-term synaptic plasticity in fetal alcohol syndrome. Proc Natl Acad Sci U S A 2007; 104:9858-63. [PMID: 17535929 PMCID: PMC1887541 DOI: 10.1073/pnas.0607037104] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
In cerebellum and other brain regions, neuronal cell death because of ethanol consumption by the mother is thought to be the leading cause of neurological deficits in the offspring. However, little is known about how surviving cells function. We studied cerebellar Purkinje cells in vivo and in vitro to determine whether function of these cells was altered after prenatal ethanol exposure. We observed that Purkinje cells that were prenatally exposed to ethanol presented decreased voltage-gated calcium currents because of a decreased expression of the gamma-isoform of protein kinase C. Long-term depression at the parallel fiber-Purkinje cell synapse in the cerebellum was converted into long-term potentiation. This likely explains the dramatic increase in Purkinje cell firing and the rapid oscillations of local field potential observed in alert fetal alcohol syndrome mice. Our data strongly suggest that reversal of long-term synaptic plasticity and increased firing rates of Purkinje cells in vivo are major contributors to the ataxia and motor learning deficits observed in fetal alcohol syndrome. Our results show that calcium-related neuronal dysfunction is central to the pathogenesis of the neurological manifestations of fetal alcohol syndrome and suggest new methods for treatment of this disorder.
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Affiliation(s)
- Laurent Servais
- Laboratory of Neurophysiology, Université Libre de Bruxelles (ULB), B-1070 Brussels, Belgium.
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49
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Abstract
Maternal alcohol consumption during pregnancy can cause serious birth defects, of which fetal alcohol syndrome (FAS) is the most devastating. Recognized by characteristic craniofacial abnormalities and growth deficiency, this condition produces severe alcohol-induced damage in the developing brain. FAS children experience ataxia; deficits in intellectual functioning; and difficulties in learning, memory, problem solving, and attention. Multiple aspects of central nervous system development can be affected by alcohol exposure, but the most striking abnormalities are neuronal and glial migration. Little is known about cellular mechanisms by which alcohol affects the migration of immature neurons. Recently, it has been found that Ca(2+) signaling and cyclic nucleotide signaling are the central targets of the action of alcohol in neuronal cell migration. Most importantly, the aberrant migration of immature neurons caused by alcohol exposure is significantly ameliorated by controlling the activity of these second-messenger pathways. In this Mini-Review, we first describe how alcohol exposure impairs the migration of cerebellar granule cells and then discuss the signaling mechanisms involved.
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Affiliation(s)
- Tatsuro Kumada
- Department of Neurosciences, Lerner Research Institute, The Cleveland Clinic Foundation, Cleveland, Ohio 44195, USA
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Cameron DB, Galas L, Jiang Y, Raoult E, Vaudry D, Komuro H. Cerebellar cortical-layer-specific control of neuronal migration by pituitary adenylate cyclase-activating polypeptide. Neuroscience 2007; 146:697-712. [PMID: 17383102 PMCID: PMC1951536 DOI: 10.1016/j.neuroscience.2007.02.025] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2006] [Revised: 01/30/2007] [Accepted: 02/04/2007] [Indexed: 12/21/2022]
Abstract
Migration of immature neurons is essential for forming the cortical layers and nuclei. Impairment of migration results in aberrant neuronal cytoarchitecture, which leads to various neurological disorders. Neurons alter the mode, tempo and rate of migration when they translocate through different cortical layers, but little is known about the mechanisms underlying this process. Here we show that endogenous pituitary adenylate cyclase-activating polypeptide (PACAP) has short-term and cortical-layer-specific effects on granule cell migration in the early postnatal mouse cerebellum. Application of exogenous PACAP significantly slowed the migration of isolated granule cells and shortened the leading process in the microexplant cultures of the postnatal day (P)0-3 cerebella. Interestingly, in the cerebellar slices of P10 mice, application of exogenous PACAP significantly inhibited granule cell migration in the external granular layer (EGL) and molecular layer (ML), but failed to alter the movement in the Purkinje cell layer (PCL) and internal granular layer (IGL). In contrast, application of PACAP antagonist accelerated granule cell migration in the PCL, but did not change the movement in the EGL, ML and IGL. Inhibition of the cAMP signaling and the activity of phospholipase C significantly reduced the effects of exogenous PACAP on granule cell migration. The PACAP action on granule cell migration was transient, and lasted for approximately 2 h. The duration of PACAP action on granule cell migration was determined by the desensitization of its receptors and prolonged by inhibiting the protein kinase C. Endogenous PACAP was present sporadically in the bottom of the ML, intensively in the PCL, and throughout the IGL. Collectively, these results indicated that PACAP acts on granule cell migration as "a brake (stop signal) for cell movement." Furthermore, these results suggest that endogenous PACAP slows granule cell migration when the cells enter the PACAP-rich PCL, and 2 h later the desensitization of PACAP receptors allows the cells to accelerate the rate of migration and to actively move within the PACAP-rich IGL. Therefore, endogenous PACAP may provide a cue that regulates granule cell migration in a cerebellar cortical-layer-specific manner.
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Affiliation(s)
- D. Bryant Cameron
- Department of Neurosciences, Lerner Research Institute, The Cleveland Clinic Foundation, Cleveland, Ohio 44195, USA
| | - Ludovic Galas
- European Institute for Peptide Research (IFRMP 23), Laboratory of Cellular and Molecular Neuroendocrinology, Institute National de la Sante et de la Recherche Medicale U-413, University of Rouen, Mont-Saint-Aignan, France 76821
| | - Yulan Jiang
- Department of Neurosciences, Lerner Research Institute, The Cleveland Clinic Foundation, Cleveland, Ohio 44195, USA
| | - Emilie Raoult
- European Institute for Peptide Research (IFRMP 23), Laboratory of Cellular and Molecular Neuroendocrinology, Institute National de la Sante et de la Recherche Medicale U-413, University of Rouen, Mont-Saint-Aignan, France 76821
| | - David Vaudry
- European Institute for Peptide Research (IFRMP 23), Laboratory of Cellular and Molecular Neuroendocrinology, Institute National de la Sante et de la Recherche Medicale U-413, University of Rouen, Mont-Saint-Aignan, France 76821
| | - Hitoshi Komuro
- Department of Neurosciences, Lerner Research Institute, The Cleveland Clinic Foundation, Cleveland, Ohio 44195, USA
- Department of Molecular Medicine, The Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, Ohio 44195, USA
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